Luting- jack



March 4, 1924. 1,485,516

J- J- MIZER LIFTING JACK Filed Nov. 7. 1921 Patented Mar. 4, 1924.

UNi'lED STATES Pi'i'rEltl'l FFICE.

JOSEEH J. MIZER, OF RACEENE, WISCONSIN, ASSIGNGR. T WALKER MANUFACTUR- ING COMPANY, OF R13-CINE, WSOONS, A COREATION GF WISCQNSIN.

.LIFTING MLCK Application nled November 7, 1921.

To all whom t may concern:

Be it known that l, JosnPH d. Mrznn, a citizen of the United States, residing at Racine, in the county of Racine and State of Wisconsin, have invented certain new and useful Improvements in Lifting Jacks, of which the following is a specification;

My invention relates to lifting jacks and it has for its principal object the provision of a new and improved arrangement and construction comprising two telescoping screws by which the load supporting member is raised and lowered. It is one of the objects of my invention to provide a construction of this type in whichrsuch screws operate successively, the friction in the operation of the device being thus restricted to a single screw at any given point in the operation while at the same time the reach of the jack as a whole corresponds to that of the well known double screw jacks in which both screws are operated at the same time with a consequent heavy friction. It is another object of my invention to provide in a jack of this type for swinging the operating handle around a vertical axis with respect to the standard so as to provide for the positioning of the handle at the most convenient point for operation on a particu- 30 lar job. lt is still another object of my invention to provide that such adjustment of the position of the handle can be effected at any time during the raising operation. It is another object ofmy invention to improve devices of this type in sundry details hereinafter pointed out. The preferred means by which l have accomplished my several objects are illustrated in the drawings and are hereinafter specilically described. That which I believe to be new and desire to cover by Letters Patent is set forth in the claims.

lin the drawings,-

Fig. 1 is a central vertical section through the preferred embodiment of my invention.

Fig. 2 is a side elevation of the lower end portion of the 'jack and Fig. 3l is a horizontal section taken at line 3-3 of Fig. 2.

Referring to the several figures of the drawings in which corresponding parts are indicated by the same reference characters, 10 indicates a standard in the form of a sleeve cast integrally with a base 11. The upper end of the sleeve 10 is in the form of a nut, being provided with interior screw Serial No. 513,341.

' threads for cooperation with a hollow screw olubly mounted a load supporting member 16of any approved type, a thrust bearing 17 being interposed between the load supporting member and the screw.

Revolubly mounted upon the nut 14: is a cap 18 which forms the upper closure member of a housing 19 which extends about the standard 10 in spaced relation thereto. It will be appreciated that by mounting the housing -19 upon the nut 14 such housing will be supported by the hollow screw 12. Forrotating the nut 14 for edecting the operation of the jack as hereinafter described, I have formed integrally with the nut a beveled gear 20 which meshes with a beveled gear 21 keyed upon a shaft 22 which is journalled in a suitable bearing provided by the housing 19. A thrust bearing 23 of any suitable type is interposed between the beveled gear 21 and the wall of the housing. Mounted upon the outer end of the shaft 22 for rotating it there is a hand crank or lever 24. of any approved type.

As is clearly shown in Fig. 1, the hollow screw 12 is provided at one side with a. vertically extending slot 25 within which a pin 26 extends from one side of the inner screw 15 and is free to move vertically therein.

With the parts in the position shown in F ig. 1, the jack is adapted to be placed in position beneath a load to be raised, as will be readily understood. As is clearly shown in Figs. 2 and 3, the outer wall of the standard 10 is luted vertically so as to provide a plurality of vertically extending grooves into any one of which a screw v27 carried by the housing 19 is adapted to be projected by rotating the screw through the medium of the head 28. When the jack has been placed in position under a load, the screw 27 can be retracted so as to permit the housing 1,9y to `be rotated with respect to the standard 1`Offor bringing the hand crank 24 to the most convenient position for operation, the handle 24 being left free to rotate so as to permit the gear 21l to travel about the gear 20. lVhen the housing has been rotated to the desired point, the screw 27 is again moved into position to enter the adjacent vertical groove of the standard 10 for preventing further rotation of the housing 19 while at the same time permitting vertical movement of the housing as hereinafter described.

When the jack has been adjusted to operative'position, power is applied through the hand crank 24 for rotating the shaft 22 and vthe gear 21, serving to cause a. rotation of the gear120 and the nut 14 for causing an upwardV movement of the inner screw 15 with respect to the outer screw y12. As will be readily appreciated, this upward movement of the screw 15' with respect to the screw 12 is'effected'independently of any rotation of either screw, the screw 12 remaining stationary while the screw 15 moves upward carrying the kpin 26 upwardly along the slot 25. Then the pin 26 reaches the upper end of the slot 25, however, the inner screw 15l is held against further upward movement with respect to the screw 12, whereupon the continued rotation of the nut 14 in the same direction as before causes the two screws to rotate in unison, causing the screw 12to move upwardly through the nut portion of the standard 10. It is thus seen that the screws 12 and 15 are moved upwardly in succession. vThat is to say, the screw 15 is 'first moved upwardly while the screw 12 is stationary, and the screw 12 is movedupwardly'aftertlie screw 15 reaches the limit of its upward movement with respect to the screw 12. The screw 1-5 continues to move upwardly after the screw 12 starts its upward movement, but this continued upward movementy of the screw 15 is merely incidental tothe support of the screw llrby the screw 12. When it is desired to lower the load supporting member 16 isleflectedby1 a rotation of the shaft in'the?reversel'directiol th'IOllgh the medum' ofthe hand ,crank24 As will be readily understood, upon the commencement of the reverse rotation of the nut 14 'for a lowering operation, the screw 15 is first moved downwardly to they limit ofits1notion with reepeot to the screw 12 during which movement neither. of the screws is causedto, ro tate'` Whenthescrew 15 reaches the limit ot't's do ward. movement with respect to the',l screwglZ, 'the continued ref Y. ',SQTQCktiOI-if fth. mit 14 causes brot-h screwsn to, rotate liIiSDIl, carrying'-the l2-@Owe ardlrftlro'uah tlenlltporf 16 is supported by the screw in `epend ently of the housing 19,.it will be apparent that the adjustment of the housing 19 about its vertical axis can be eiiected at any time during the raising operation for adjusting the position of the hand crank without affecting in any way the raising operation.

I claim:

1. A lifting ack including in combination a standard, screws nested therein, means for moving said screws successively under certain conditions and together under other conditions, a housing rotatably mounted on and movable with one of said screws and enveloping said standard, and means carried by said housing for effecting movement of said screws in the desired manner.

2. A lifting jaclr comprising a standard, a screw supported by said standard, a second screw supported from said iirst named screw, a load supporting member carried by said second screw, and means carried by the first named screw for raising said screws successively with respect to said standard.

3. A lifting jack comprising a standard, a screw supported by said standard, a second screwsupported from said first named screw, an anti-friction bearing interposed between said two screws, a load supporting member carried by said second screw, and means for raising said screws successively with respect to said standard.

4. A lifting jack comprising a standard, a plurality of screws disposed one within another in said standard, means for preventing relative rotation of said screws, a housing rotatably mounted on and movable with one ofI said screws and surrounding the standard,l and means on said housing for causing longitudinal movement of said screws for load lifting purposes.

5. A lifting jack comprising a standard, a screw supported by said standard, a second screw supported from said first named screwv`v a load supporting member carried by said second screw, and a nut engaging said second screw and rotatably supported by said first-named screw.

6. A lifting jack comprising a base, a standard rising from the base, a hollow screw in threaded engagement with said standard, a nut supported on the upper end of said screw, a second screw in threaded engagement with said nut and extending into said firstscrew, said first and second screws being provided with means forpreventing relative rotation therebetween, a load supporting member on the end of said second screw, a housing supported by and depending from said nut surrounding said standard, and means carried by said housing in cooperative engagement with said nut for rotating'the latter to move said screws longitudinally for load lifting purposes.

""7.' A'liftin'g jack comprising in combination a base, a standard rising from the base, a hollow screw in threaded engagement with said standard, a nut separate from and supported on the upper end of said screw, a second screw in threaded engagement with said nut and extending into said hol low screw, said first and second screws beprovided with means for preventing relative rotation ltherebetween, a load supporting member on the end of said second screw, and means cooperating with said nut for rotating the same to move said screws for load moving purposes.

8., A lifting jack including in combination, an upright hollow standard, a hollow screw in threaded engagement with the upper end of said standard, a nut supported by said screw and separated therefrom by an anti-friction bearing, a second screw in threaded engagement with said nut and arranged to enter said first screw, a load engaging member carried by said second screw, a gear associated with said nut, a housing carried by and depending :from said nut and surrounding said standard, a gear journaled in said housing cooperating with the first mentioned gear, and means exteriorly of the housing for actuating said gears to rotate said nut for moving said screws for lifting purposes.

9,. A lifting jack comprising in combination a standard, a plurality of screws disposed one within another in said standard, means cooperating with said screws for preventing relative rotation therebetween and vfor limited vertical movement with respect to one another, a housing movable with one of said screws and surrounding said standard, means on said housing for causing longitudinal movement of said screws for load lifting purposes, said housing being adapted for rotative movement about its supporting screw for assuming di'erent angular positions with respect to said standard, and means 'for locking said housing in adjusted angular position.

l0. A lifting jack comprising a standard, a hollow screw supported by said standard and adapted upon rotation to move vertically with respect to the standard, a second screw loosely mounted within said first named screw, means for limiting the vertical movement of said second screw with respect to the first named screw and for holding said screws against rotation with respect to each other, a nut supported by said first named screw and engaging the threads of the second screw, a load supporting member carried by said second screw, a housing sup ported from said nut and slidable vertically with respect to said standard, means for holding said housing against rotation with respect to said standard, a hand crank mounted on said housing, and connections between said crank and said nut for rotating the nut adapted first to cause a vertical movement of the second screw to the limit of its motion with respect to the first named screw and adapted then to cause rotation of the screws in unison for raising them both with respect to the standard.

1l. A lifting jack comprising a standard, a hollow screw supported by said standard and adapted upon rotation to move vertically with respect to the standard, a second screw loosely mounted within said first named screw, means 'for limiting the vertical movement of said second screw with respect to the first named screw and for holding said screws against rotation with respect to each other, a nut supported by said first named screw and engaging the threads of the second screw, a load supporting member carried by said second screw, a

housing supported from said nut and slidable vertically with respect to said standard, means for holding said housing in any desired adjusted position about said standard, and operating means carried by said housing for rotating said nut adapted first to cause vertical movement of the second screw to the limit of its motion with respect to the first named screw and adapted then to cause rotation of the screws in unison for raising both of them with respect to the standard.

12. A lifting jack comprising a standard, a hollow screw supported by said standard and adapted upon rotation to move vertically with respect to the standard, a second screw loosely mounted within said first named screw, means for limiting the vertical movement of said second screw with respect to the first named screw and for holding said screws against rotation with respect to each other, a nut supported by said first named screw and engaging the threads of the second screw, a load supporting member carried by said second screw, a housing supported from said nut and slidable vertically with respect to said standard, means for `f` holding said housing against rotation with respect to said standard, a gear carried by said nut, a shaft journaled in said housing at one side thereof, a gear fiXedly mounted on said shaft and meshing with said first named gear, and means for rotating said shaft for driving said nut adapted lirst to cause vertical movement of the sec ond screw to the limit of its motion with respect to the first named screw and adapted L raising both of said screws in unison and for raising one ofr the screws with respect to the other for carrying said load supporting member upwardly, means for operating said screw raising means, said operating means being adjustable about said standard independently of the load carried by said load supporting member, and means for locking said operating means in adjusted position.

14. A lifting jack comprising a'standard, a screw supported by said standard, a second screw supported from said iirst named screw, a load supporting member carried by said second screw, means adapted upon rotation in one direction to act alternately for raising both of said screws in unison and for raising one of the screws with respect to the other for carrying said load supporting member upwardly, means for operating said screw raising means, said operating means being adjustable about said standard independently of any rotation of said rotary screw raising means, and means for locking said operating means in adjusted position.

JOSEPH J. MIZER. 

